Continuous plate making method for photosensitive resin plate and device thereof

ABSTRACT

A continuous plate making method for a photosensitive resin plate which comprises setting the photosensitive resin plate on a surface of an endless belt or a setting plate which moves on a substantially circular orbit, and continuously subjecting the plate to, at least, washing out, drying and then post light exposure steps as the belt or the setting plate moves continuously. A device for carrying out this method is also disclosed.

This application is a continuation-in-part application of ApplicationSer. No. 707,268 filed Mar. 1, 1985 now U.S. Pat. No. 4,733,260.

FIELD OF THE INVENTION

The present invention relates to a continuous plate making method forphotosensitive resin plates and a device thereof. More particularly,according to the present invention, photosensitive resin plates can becontinuously and automatically made into engraved plates such asprinting plates and the like without requiring a large space.

BACKGROUND OF THE INVENTION

Usually, a photosensitive resin plate is composed of a support materialsuch as a plastic film, a metallic plate or the like, and aphotosensitive resin layer formed on the surface of the supportmaterial. In order to make a photosensitive resin plate into an engravedplate such as a printing plate or the like, an original film iscontacted on the surface of the photosensitive resin layer of the plateand an actinic light is irradiated to insolubilize the exposed part ofthe plate. Then, the non-exposed part is washed out with a solvent andthereafter, the plate is subjected to work up steps such ashydro-extracting, drying, post light exposure, etc. to form a printingplate or the like.

At present, a method mainly employed in the above plate making is abatch-wise method wherein each of the steps of washing out,hydro-extracting, drying and post light exposure are carried outseparately by using different devices and, during the plate making, theplate is manually moved one step to another. For example, aphotosensitive resin plate which has been exposed to light is set in awash-out device where the non-exposed part thereof is washed out.Thereafter it is moved to a dryer by hand to dry the plate.

In order to constantly and quickly make photosensitive resin plates intoengraved plates such as printing plates of stable high quality, acontinuous and automatic plate making method has been required. In thisregard, the development of a continuous plate making method has recentlybeen started, wherein the above steps are continuously carried out whilea photosensitive resin plate set on a surface of a belt or a so-calledsetting plate is moved horizontally. For carrying out this method, therehas been developed a combination of devices wherein devices for eachstep such as washing out, hydro-extracting, drying, post light exposureand the like are arrayed in order of the steps on the same levelparallel with the floor. The photosensitive resin plate is set on achain or a setting plate fixed to a chain and the chain is drivenintermittently or continuously.

However, in this combination of devices, there are drawbacks such as therequirement for a large space for arraying the devices, and poor workingefficiency due to the long distance between openings for feeding andremoving the photosensitive resin plate.

In order to save labor as much as possible and to reduce the spacerequirement, another continuous plate making method and a device thereofhave been proposed (Japanese Patent Publication No. 21339/1980). In thismethod, a photo-sensitive resin plate is set on a peripheral surface ofa cylindrical drum rotating intermittently and all the steps for platemaking are completed during one rotation cycle of the drum.

However, in the above method and device, the rotation and stopping ofthe drum are repeated alternately at every angle of 120° because ofintermittent rotation and each step is carried out at the same timewhile the drum is stopped. Therefore, each step should be completedwithin the same period of time. Further, because each step is carriedout while the photosensitive resin plate and the means for the treatmentof each step are in one fixed position, it is difficult to effect thetreatment of each step uniformly. In addition, the photosensitive resinplate is removably set on the drum by means of electromagnets and onlyup to 3 sheets of photosensitive resin plates can be treated per onerotation cycle.

OBJECTS AND SUMMARY OF THE INVENTION

One object of the present invention is to provide an improved continuousplate making method for a photosensitive resin plate which does not havedrawbacks such as those of the conventional plate making methodsdescribed above.

Another object of the present invention is to provide a device forcarrying out the continuous plate making method of the presentinvention.

These objects as well as other objects and advantages of the presentinvention will become apparent to those skilled in the art from thefollowing description and the accompanying drawings.

According to the present invention, there is provided a continuous platemaking method for a photosensitive resin plate which comprises settingthe photosensitive resin plate on a surface of an endless belt or asetting plate which moves in a substantially circular orbit, preferably,on an inside or outside surface thereof so that the inside surfacethereof radially faces the inside of the orbit, and continuouslysubjecting the resin plate to, at least, washing out, drying and postlight exposure steps as the belt or the setting plate movescontinuously. The device of the present invention comprises a carriermeans arranged in a substantially circular shape, at least one endlessbelt or a setting plate which receives a photosensitive resin plate andmoves along the carrier means on an orbit defined by the carrier means,preferably, the inside surface of the belt or the setting plate radiallyfacing the inside of the orbit, and a means for subjecting the plate to,at least, washing out, drying and post light exposure steps arrangedaround the orbit of the belt or the setting plate so that the treatmentof each step is carried out in order as the belt or the setting platemoves continuously.

BRIEF EXPLANATION OF DRAWINGS

FIG. 1 illustrates a schematic cross section of a preferred embodimentof the continuous plate making device of the present invention.

FIG. 2 illustrates a schematic cross section of another preferredembodiment of the continuous plate making device of the presentinvention.

FIG. 3 illustrates a schematic cross section of still another preferredembodiment of the continuous plate making device of the presentinvention.

FIG. 4 illustrates a schematic cross section of still another preferredembodiment of the continuous plate making device of the presentinvention.

FIG. 5 illustrates a schematic perspective view of an example of asetting plate.

FIG. 6 illustrate a schematic cross section of the setting plate of FIG.5.

PREFERRED EMBODIMENTS OF THE INVENTION

In one preferred embodiment, the continuous plate making method of thepresent invention is carried out by setting a photosensitive resin platewhich has been contacted with an original film and exposed to an actiniclight on the inside surface of the belt or the setting plate moving on avertical circular orbit so that the inside surface thereof radiallyfaces the inside of the orbit. The device illustrated in FIG. 1 is usedfor carrying out this embodiment.

In FIG. 1, the device includes an endless belt 1 which is verticallyarranged and is driven at a constant speed by means of a chain 2 and amotor 3. The belt 1 continuously moves in a substantially circular orbitalong carrier means 4 in a counterclockwise direction as shown by thearrows shown in FIG. 1. The carrier means in FIG. 1 comprises the pairsof rollers. However, for example, it may be pairs of guides or, whenusing one or more setting plates instead of the endless belt, it may bea tenter or the like to which each side of the setting plate is fixed bymeans of rails, pins, clips, etc. The surface of the endless belt 1 orthe setting plate on which the photosensitive resin plate set radiallyfaces the inside of the orbit and is preferably made of a plastic layerhaving stickiness or a magnetic rubber.

The photosensitive resin plate 5 which has been already exposed to anactinic light is set on the inside surface of the belt 1 moving on avertical circular orbit defined by the carrier means 4 at the positionshown by the letter A. As the belt moves, the pair of rollers 6removably joins the plate 5 to the belt 1.

In the device of FIG. 1, the means for subjecting the plate to washingout, drying and post light exposure is divided into four sections shownby the letters B through E.

In section B, the non-exposed part of the plate 5 is washed out. Adeveloping solution (i.e., a solvent for dissolving or dispersing thenon-exposed part of the photosensitive resin layer of the plate such aswater, an aqueous alkaline solution, alcohol, etc.) which is deliveredfrom a tank 7 by means of a pump 8 is poured onto brushes 10 and 10'from nozzles 9 and 9'. The brushes 10 and 10' are driven by motors 11and 11' and the non-exposed part of the photosensitive resin plate 5 iscontinuously washed out by eccentric or rotary motion of the brushes.Then, the pair of pinch rolls 12, which have porous surfaces, squeezesout the solution remaining on the plate 5. The solution returns to thetank 7. By the way, in the washing out step of the section B, sprayingcan be employed instead of brushing, by spraying the developing solutionfrom plural spray nozzles to wash out the non-exposed part. Further, inthe case of a thin plate, it is possible to actuate only one of thebrushes 10 or 10'.

In section C, rinsing is carried out. A fresh rinsing solution (e.g.,fresh water, alcohol, etc.) which is delivered from a tank 13 by meansof a pump 14 is sprayed onto the plate and the belt from nozzles 15 and15' to completely rinse out the developing solution, the non-exposedpart of the photosensitive resin layer and the like remaining on thesurfaces of the plate and the belt. Thereafter, the pair of pinch rolls16 squeezes out the fresh rinsing solution remained on the plate. Therinsing solution is returned to the tank 13.

Drying is carried out in section D. As the plate and a belt move, hotair is blown out from a blower 17 through plural openings 18 tocontinuously dry the plate 5.

In section E, post light exposure is carried out. Actinic light sources(for example chemical lamps, high pressure mercury lamps etc.) 19 areprovided along the inside of the belt 1 and the entire surface of theplate 5 on the belt 1 is exposed to the actinic light to furthersolidify the surface of the plate.

After continuously moving on the substantially circular orbit tocomplete all the steps, the photosensitive resin plate 5 isautomatically removed from the belt 1 at the position shown by theletter F by means of the bend of a belt 1 and the scraper 20. Thescraper 20 guides the plate to a receiving box 21. It is desirable tobend the belt 1 toward the outside of its circular orbit at the positionF to such a degree that the angle between the belt and the tangent lineof the circular orbit at the position F is 5° or more, preferably, 10°or more, so that the plate 5 is automatically and readily removed fromthe belt.

In another preferred embodiment, the continuous plate making method ofthe present invention is carried out by setting a photosensitive resinplate which has been contacted with an original film and exposed to anactinic light on the outside surface of the belt or the setting platemoving in a vertical circular orbit so that the outside surface thereofis radially facing the outside of the orbit. The device illustrated inFIG. 2 is used for carrying out this embodiment.

As in the device of FIG. 1, the device of FIG. 2 has an endless belt 1which is vertically arranged and is driven at a constant speed by meansof a chain 2 and a motor 3. The belt 1 continuously moves in asubstantially circular orbit along carrier means 4 in a counterclockwisedirection.

The photosensitive resin plate 5 which has been already exposed to anactinic light is placed on the stand 22 and fed to the outside surfaceof the belt 1 moving in a vertical circular orbit defined by the carriermeans 4 at the position shown by the letter A. The pair of rollers 6removably joins the plate 5 to the belt 1.

Likewise, the means for subjecting the plate to washing out, drying andpost light exposure is divided into four sections shown by the letters Bthrough E and each steps of washing out, rinsing, drying and post lightexposure are carried out in the respective sections. However, in thedevice of FIG. 2, the treatment in each step is effected on the outsidesurface of the belt 1 and therefore, the means for these treatments arearranged so that the treatments can be effected in such a manner.

For example, in section B, the brushes 10 and 10' are provided at theoutside of the belt 1. In section E, post light exposure is carried outby actinic light sources 19 provided along the outside of the belt 1.

In the device of FIG. 2, after completion of the treatments, thephotosensitive resin plate 5 is also automatically removed from the belt1 at the position shown by the letter F by means of a bend of the belt 1and the scraper 20. The scraper 20 guides the plate to a receiving box21. However, in this case, the belt is bent toward the inside of itscircular orbit. It is desirable to bend the belt 1 toward the inside atthe position F to such a degree that the angle between the belt and thetangent line of the circular orbit at the position F is 5° or more,preferably, 10° or more.

The device of FIG. 3 is designed for using a setting plate. It hasplural pairs of rollers 4 which are arranged and rotated by suitabledrive means such as a combination of a moter and a belt (not shown) sothat a material passing through their gaps goes along a substantiallycircular orbit as in the device of FIG. 1.

The photosensitive resin plate 5 which has been already exposed to anactinic light is set on the surface of a setting plate 23 and fed to thegap between the pair of rollers 6 in such a manner that the surface ofthe photosensitive resin plate 5 is faced to the radially inside of theorbit. As the rollers rotate, the setting plate moves toward the nextgap of the next pair of the rollers in turn. Thus, the setting platetogether with the photosensitive resin plate is passing through the gapsof the pairs of rollers 4 along the orbit and the photosensitive resinplate 5 is subjected to the same treatment as in the device of FIG. 1.After treatment, the the photosensitive resin plate 5 set on the settingplate is guided to the receiving box 21 by means of the scraper 20.

The device of FIG. 4 is the same as that of FIG. 3 except that thephotosensitive resin plate 5 to be treated is faced to the radiallyoutside of the orbit as in the device of FIG. 2.

One example of the setting plate 23 is shown in FIGS. 5 and 6. Thissetting plate is in a rectangular shape (e.g., 680 mm×850 mm) and has abase 24 composed of a heat-resistant plastic sheet such as apolycarbonate sheet, and a sheet 25 attached to the base 24. The sheet25 is made or rubber containing magnetic particles or foamedpolyurethane having, for example, an adherent surface, and receives thephotosensitive resin plate 5.

The continuous plate making method and the device of the presentinvention as described above can be applied to various photosensitiveresin plates regardless of their kinds, sizes and thicknesses.

Further, in the method and the device of the present invention, only anoperator who feeds photosensitive resin plates to the device is needed.The other steps such as washing out, drying and post light exposure aswell as removal of the plates from the device continuously andautomatically proceed in the device of the present invention.Accordingly, photosensitive printing plates having stable high qualitiescan be efficiently obtained.

Furthermore, there are such advantages that the space required forinstalling the device of the present invention is about 1/3 incomparison with that of a conventional device which is arrangedhorizontally because the device of the present invention is arrangedcircular, and that the operation is very easy because the feedingposition is close to the removal position.

The following Examples further illustrate the present invention indetail but are not to be construed to limit the scope thereof.

EXAMPLE 1

An original film was contacted on a surface of a photosensitive resinplate (Printight KF - 95, a polyamide resin photoengraving material tobe developed with water, manufactured by Toyo Boseki Kabushiki Kaish;size: A2 (420 mm×594 mm); thickness: 1.20 mm) and the plate was exposedto a 4 KW high pressure mercury lamp for 40 seconds to reproduce animage. According to this procedure, several photosensitive resin plateswere exposed to the lamp to reproduce images.

The exposed plates were fed to the device shown in FIG. 1 or 2 at 3.5minute intervals. Although, it took about 15 minutes until the firsttreated plate was received in the receiving box, the subsequent plateswere surely obtained at regular time intervals of 3.5 minutes.

Each of the resultant printing plates had an image which was a precisereproduction of that of the original film and had good relief having adeep depth of relief.

EXAMPLE 2

According to the same procedure as in Example 1, several sheets ofPrintight KF - 95 (size: A0 (841 mm×1,189 mm)) were exposed to the highpressure mercury lamp and fed to the device of FIGS. 1 or 2 at 7 minuteintervals. Although it took about 15 minutes until the first treatedplate was received in the receiving box, the subsequent plates whichwere printing plates having high quality were obtained at regular timeintervals of 7 minutes.

EXAMPLE 3

Conditions for each step for washing out, drying and post light exposureare different from each other depending upon the thickness of aphotosensitive resin plate to be treated. Accordingly, the sameprocedure as in Example 1 was repeated by using the device of FIGS. 1 or2 and varying the conditions for each step as shown in Table 1. As aresult, printing plates having high qualities as described in Example 1were continuously obtained.

                  TABLE 1                                                         ______________________________________                                        Thickness   1.52     1.20   0.95   0.70 0.43                                  of plates (mm)                                                                            1.52     1.20   0.95   0.70 0.43                                  Time for washing                                                                          220      165    120    100  40                                    out (sec.)                                                                    Time for drying                                                                           7        6      5      5    5                                     (60° C. hot air,                                                       min)                                                                          Time for post                                                                             7        6      5      5    5                                     light exposure                                                                (min.)                                                                        ______________________________________                                    

EXAMPLE 4

According to the same procedure as in Example 1, photosensitivepolyvinyl alcohol plates (Miraclon MF 94A manufactured by Tokyo OhokaKogyo Kabushiki Kaisha; size: A2) were treated. As a result, printingplates were continuously obtained every 3.5 minutes.

EXAMPLE 5

According to the same procedure as in Example 2, photosensitivepolyamide plates (Torelief 95 BS manufactured by Toray Kabushiki Kaisha;size: A0) were treated As a result, printing plates were continuouslyobtained every 7 minutes.

EXAMPLE 6

According to the same procedure as in Example 1, several sheets ofPrintight KF - 95 (size: A0 (841 mm×1,189 mm)) are exposed to the highpressure mercury lamp and fed to the device of FIGS. 3 or 4 at 7 minuteintervals to make printing plates.

What is claimed is:
 1. A continuous plate making method for aphotosensitive resin plate, which comprises the steps of: setting thephotosensitive resin plate on an inside surface of a setting plate whichmoves in a substantially circular orbit so that the inside surfacethereof is radially faced to the inside of the orbit; and continuouslysubjecting the photosensitive resin plate to, at least, washing out,drying and then post light exposure as the setting plate movescontinuously.
 2. A continuous plate making device for a photosensitiveresin plate which comprises a carrier means arranged in a substantiallycircular shape, at least one setting plate which receives aphotosensitive resin plate on its surface and moves along the carriermeans on an orbit defined by the carrier means, wherein the surface ofthe setting plate radially faces the inside of the orbit thereof, and ameans for subjecting the photosensitive plate to, at least washing out,drying and post light exposure steps arranged around the orbit of thesetting plate so that the treatment of each step is carried out in orderas the setting plate moves continuously.
 3. A continuous plate makingdevice for a photosensitive resin plate which comprises a carrier meansarranged in a substantially circular shape, at least one setting platewhich receives a photosensitive resin plate and moves along the carriermeans on an orbit defined by the carrier means, said setting platehaving a sticky surface on which the photosensitive resin plate isreceived and a means for subjecting the photosensitive plate to, atleast, washing out, drying and post light exposure steps arranged aroundthe orbit of the setting plate so that the treatment of each step iscarried out in order as the setting plate moves continuously.
 4. Acontinuous plate making method for a photosensitive resin plate, whichcomprises the steps of: setting the photosensitive resin plate on anoutside surface of a setting plate which moves in a substantiallycircular orbit so that the outside surface thereof is radially faced tothe outside of the orbit; and continuously subjecting the photosensitiveresin plate to, at least, washing out, drying and then post lightexposure as the setting plate moves continuously.
 5. A continuous platemaking device for a photosensitive resin plate which comprises a carriermeans arranged in a substantially circular shape, at least one settingplate which receives a photosensitive resin plate on its surface andmoves along the carrier means on an orbit defined by the carrier means,wherein the surface of the setting plate radially faces the outside ofthe orbit thereof, and a means for subjecting the photosensitive plateto, at least washing out, drying and post light exposure steps arrangedaround the orbit of the setting plate so that the treatment of each stepis carried out in order as the setting plate moves continuously.
 6. Acontinuous plate making method for a photosensitive resin plate, whichcomprises the steps of: setting the photosensitive resin plate on anoutside surface of an endless belt which moves in a substantiallycircular orbit so that the outside surface thereof is radially faced tothe outside of the orbit; and continuously subjecting the photosensitiveresin plate to, at least, washing out, drying and then post lightexposure as the belt moves continuously.
 7. A method according to claim6, wherein the photosensitive resin plate is automatically, removed fromthe surface of the endless belt by directing the belt toward the insideof its circular orbit so as to vary the curvature radius of the circularorbit after the photosensitive resin plate has been subjected to washingout, drying and post light exposure.